Chronologically speaking, this is Ingmar Bergman's fourth masterpiece after Sawdust and Tinsel, Smiles of a Summer Night, and The Seventh Seal.
This is a film I meet up with at least once a year. Along with Citizen Kane and The Magnificent Ambersons, this films helps form Orson Welles' Holy Trinity (his three best films) in my opinion. The three+ minute opening one shot is one for the ages! Henry Mancini and Russell Metty both work their considerable movie mojo in their respective original score and cinematography departments to perfection.
If you choose to enter this completely absurd black comedy from director Mike Nichols, I would advise you to avoid wearing your logic cap for this wild ride since in realistic terms it makes next to no sense. Instead approach it with an open mind that welcomes its touches of surreal darkly- comedic contrarian flourishes, and you'll be amply rewarded. They honestly don't make films like this any longer. It would make for a fantastic double feature with another brilliant dark comedic take on the insanity of war released in 1970, Robert Altman's MASH.